Will not take a charge! Low Side too High

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Will not take a charge! Low Side too High

Postby jbaaron » Fri Sep 16, 2016 11:04 pm


I installed a new compressor, drier, liquid line, manifold hose, and O-Rings. The condenser and evaporator were flushed. Once, I got new parts in, I pull a vacuum for 60 minutes and it was still holding a couple of hours later.

I began charging the system with R134 and it would not take a charge. I thought it should at least pull some refrigerant in with engine off and a vacuum. Finally, I started the car and elevated the can way above the manifold and I saw refrigerant slowly going in. The compressor finally kicked on but it was cycling quickly. As I continued to add refrigerant, the low side pressure keep rising as did the high side. After 14 to 16 ounces, I had to stop because the low side was heading towards 90 psi while the high side was nearing 200psi. Also, the compressor began to make a strange noise. I was thinking there is a restriction somewhere or the compressor was defective. I started over from scratch and the same thing happened.

I noticed while I was looking at the system for issues that the LH (Driver Side) fan was not on while the other side was running. I believe the LH (Driver Side) is for the radiator and the RH (Passenger Side) is for the condenser. I’m not sure but I would think both of these fans need to be running while the A/C is on or the coolant reaches a specific temp. I have no idea how long the fan has been dead but now I wonder if it had any involvement with the previous A/C system failure. Anyways, I looked at all fuses and relays and all were okay. I removed the connector and checked the voltage after turning the A/C on. I saw around 12 VDC which indicated a failed fan. I check both fans against the battery and sure enough, the LH was bad and the RH is still good. I’m not sure how to test the higher speed on these fans.

Will a faulty cooling fan prevent the system from taking a charge and or cause the issues I listed above? I’m picking up a new fan tomorrow and I will try to recharge the system again to see what happens. I will post the outcome regardless for anyone else who may have this problem. If I run into the same problems again, what else could it be?

I appreciate any help and or advice on this issue. I thought it was going to be smooth sailing after I had it all back together. I was wrong.

2000 Ford Taurus V6 3.0 DOHC

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